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#11977: ghc doesn't agree with its own inferred pattern type -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- GHCi, version 8.1.20160419: {{{ pattern F a <- (($ 'a') -> a) }}} {{{ pattern F :: b -> Char -> b -- Defined at /tmp/tTaa.hs:24:1 }}} Putting them together: {{{ -- tTaa.hs:25:9: error: … -- • Pattern synonym ‘F’ has one argument -- but its type signature has two -- • In the declaration for pattern synonym ‘F’ Compilation failed. pattern F :: b -> Char -> b pattern F a <- (($ 'a') -> a) }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11977 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler